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Search Publications

NIST Authors in Bold

Displaying 20176 - 20200 of 73960

Operation of an optically coherent frequency comb outside the metrology lab

March 13, 2014
Author(s)
Laura C. Sinclair, Ian R. Coddington, William C. Swann, Archita Hati, Kana Iwakuni, Nathan R. Newbury
Frequency combs can support cutting-edge measurements in areas that include optical clocks and oscillators, high-accuracy frequency and time transfer, precision spectroscopy from the UV to THz regimes, high-accuracy LIDAR, precise microwave photonics, and

Are Bragg Peaks Gaussian?

March 12, 2014
Author(s)
Boualem Hammouda
It is common practice to assume that Bragg scattering peaks have Gaussian shape. The Gaussian shape function is used to perform instrumental smearing corrections. Using Monte Carlo ray tracing simulation, the resolution of a realistic small-angle neutron

Optical amplification and pulse interleaving for low noise photonics microwave generation

March 12, 2014
Author(s)
Franklyn J. Quinlan, Frederick N. Baynes, Tara M. Fortier, Qiugui Zhou, Allen Cross, Joe Campbelll, Scott A. Diddams
We investigate the impact of pulse interleaving and optical amplification on the spectral purity of microwave signals generated by photodetecting the pulsed output of an Er:fiber-based optical frequency comb. It is shown that the microwave phase noise

Software Independent Data Mapping Tool for Structural Fire Analysis

March 12, 2014
Author(s)
Dilip K. Banerjee
In order to model the structural behavior under fire, three separate analyses need to be conducted: a) fire propagation and growth (fire modeling), b) transient heat transfer in structural members due to fire, and c) structural analysis to account for both

Twin Plane Re-entrant Mechanism for Catalytic Nanowire Growth

March 12, 2014
Author(s)
Andrew D. Gamalski, Peter W. Voorhees, Renu Sharma, Caterina Ducati, Stephan Hofmann
We observe a twin plane re-entrant based growth mechanism for Au catalyzed Ge nanowire growth using video-rate lattice-resolved environmental transmission electron microscopy. For a [112] growth direction, we find a convex, V-shaped liquid catalyst

WWVB: A Half Century of Delivering Accurate Frequency and Time by Radio

March 12, 2014
Author(s)
Michael A. Lombardi, Glenn K. Nelson
In commemoration of its 50th anniversary of broadcasting from Fort Collins, Colorado, this paper provides a history of National Institute of Standards and Technology (NIST) radio station WWVB. The narrative describes the evolution of the station, from its

(NISTIR 7988) Integrating Electronic Health Records into Clinical Workflow: An Application of Human Factors Modeling Methods to Ambulatory Care

March 11, 2014
Author(s)
Svetlana Z. Lowry, Mala Ramaiah, Emily S. Patterson, David Brick, Ayse P. Gurses, Ant Ozok, Debora Simmons, Michael C. Gibbons
This report recommendations provide a first step in moving from a billing-centered perspective (i.e., focusing on ensuring maximum and timely reimbursement) to a clinician-centered perspective where the EHR design supports clinical cognitive work, such as

Magnetic Structure of the Conductive Triangular-Lattice Antiferromagnet PdCrO 2

March 11, 2014
Author(s)
Hiroshi Takatsu, Gwilherm Nenert, Hiroaki Kadowaki, Hideki Yoshizawa, Mechthild Enderle, Shingo Yonezawa, Yoshiteru Maeno, Jungeun Kim, Naruki Tsuji, Masaki Takata, Yang Zhao, Mark Green, Collin Broholm
We performed neutron single crystal and synchrotron X-ray powder diffraction experiments in order to investigate the magnetic and crystal structures of the conductive layered triangular-lattice antiferromagnet PdCrO6d2^ with a putative spin chirality

A Novel Mechanism for Regulating the Activity of Proliferating Cell Nuclear Antigen by a Small Protein

March 10, 2014
Author(s)
Zvi Kelman, Richard Y. Huang, Zhuo Li, Jerard Hurwitz, Santangelo J. Thomas, Travis H. Hileman, Yopp C. Daniel, Jeffrey W. Hudgens
Chromosomal DNA replication requires the regulated activity of large number of proteins and complexes. Proliferating cell nuclear antigen (PCNA) protein forms a homotrimeric ring that associates with, and regulates the activity of, many proteins

Observational Results of a Multi-Telescope Campaign to Detect Interstellar Urea [(NH2)2CO]

March 10, 2014
Author(s)
Francis J. Lovas, Anthony J. Remijan, Lewis E. Snyder, Brett A. McGuire, Hsin-Lun Kuo, Leslie W. Looney, Douglas N. Friedel, G. Y. Golbiatnikov, Vadim V. Ilyushin, E A. Alekseev, S F. Dyubko, Benjamin J. McCall, Jan M. Hollis
In this paper, we present observational evidence for gas phase urea observed towards the Sgr B2(N-LMH) region. We show data covering urea transitions from 100 GHz to 250 GHz from five different observational facilities: BIMA, CARMA, the NRAO 12 m telescope

Visualizing Nanoparticle Dissolution by Imaging Mass Spectrometry

March 10, 2014
Author(s)
Christopher W. Szakal, Melissa S. Ugelow, Justin M. Gorham, Andrew R. Konicek, Richard D. Holbrook
We demonstrate the ability to visualize nanoparticle dissolution while simultaneously providing chemical signatures that differentiate between citrate-capped silver nanoparticles (AgNPs), AgNPs forced into dissolution via exposure to UV radiation, silver

Attribute Based Access Control (ABAC) Definition and Considerations

March 7, 2014
Author(s)
Chung Tong Hu
Attribute-Based Access Control (ABAC) is a logical access control methodology where authorization to perform a set of operations is determined by evaluating attributes associated with the subject, object, requested operations, and, in some cases

Analytical Capabilities of Chemiresistive Microsensor Arrays in a Simulated Martian Atmosphere

March 6, 2014
Author(s)
Kurt D. Benkstein, Phillip H. Rogers, Christopher B. Montgomery, Jerry Jin, Baranidharan Raman, Stephen Semancik
The capabilities of a chemiresistive microsensor array for detecting and identifying four trace target analytes were examined under a simulated Martian atmosphere. The simulated environment included low oxygen content (0.15 %) balanced by carbon dioxide

Fire Model Validation Eight Lessons Learned

March 6, 2014
Author(s)
Kevin B. McGrattan, Richard D. Peacock, Kristopher J. Overholt
This paper provides a summary of a decade-long effort to verify and validate a variety of different fire models used in the commercial nuclear industry. The lessons learned apply to any industry in which fire models are used in a regulatory context. The
Displaying 20176 - 20200 of 73960
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